Question on shade 3-arguments command

[Lee Hansoo <lee.hansoo@xxxxxxxxx>]

Dear Ferret users

I am trying to plot my sigma coordinates data in graphical method
using shade 3-argument command.
The script I used is like below;
-------------------------------------------------------------------------------------
let depth=h*zz                             3D(x,y,z) grid
set variable/title="Depth function"/unit=metre depth
let yrho=y[g=rho]                           4D(x,y,z,t) grid
set variable/title="Y"/unit=kilometre yrho

set view lr
shade rho[y=15,l=36], yrho[y=15,l=36], depth[x=15]
------------------------------------------------------------------------------------
and then I got error messege;
--------------------------------------------------------------------------------------------------
shade rho[y=15,l=36],depth[x=15], depth[x=15]
 **ERROR: inconsistent sizes of data regions: X coord field lies
          in different plane from data to be plotted
---------------------------------------------------------------------------------------------------
Could anyone point out some problem above and explain the shade 
or fill 3-argument command? I can not fully understand its function.


Lee HanSoo

RCDE, DPRI,
Kyoto University, 
Gokasho, Uji, Kyoto, Japan.
611-0011

Tel: 0774-38-4309
M.B : 080-5301-6649